Add utility script to stress-test mapgen

util/helper_mod/init.lua

@@ -0,0 +1,51 @@
+local mode = core.settings:get("helper_mode")
+
+if mode == "devtest" then
+
+	-- Provide feedback to script by creating files in world path
+	core.after(0, function()
+		io.close(io.open(core.get_worldpath() .. "/startup", "w"))
+	end)
+	local function callback(test_ok)
+		if not test_ok then
+			io.close(io.open(core.get_worldpath() .. "/test_failure", "w"))
+		end
+		io.close(io.open(core.get_worldpath() .. "/done", "w"))
+		core.request_shutdown("", false, 2)
+	end
+	-- If tests are enabled exit when they're done, otherwise exit on player join
+	if core.settings:get_bool("devtest_unittests_autostart") and core.global_exists("unittests") then
+		unittests.on_finished = callback
+	else
+		core.register_on_joinplayer(function() callback(true) end)
+	end
+
+elseif mode == "mapgen" then
+
+	-- Stress-test mapgen by constantly generating new area
+	local csize = tonumber(core.settings:get("chunksize")) * core.MAP_BLOCKSIZE
+	local MINP, MAXP = vector.new(0, -csize, 0), vector.new(csize*3, csize*2, csize)
+	local DIR = "x"
+	local pstart = vector.new(0, 0, 0)
+	local next_, callback
+	next_ = function(arg)
+		print("emerging " .. core.pos_to_string(pstart))
+		core.emerge_area(
+			vector.add(pstart, MINP), vector.add(pstart, MAXP),
+			callback, arg
+		)
+	end
+	local trig = {}
+	callback = function(blockpos, action, calls_rem, n)
+		if action == core.EMERGE_CANCELLED or action == core.EMERGE_ERRORED then
+			return
+		end
+		if calls_rem <= 20 and not trig[n] then
+			trig[n] = true
+			pstart[DIR] = pstart[DIR] + (MAXP[DIR] - MINP[DIR])
+			next_(n + 1)
+		end
+	end
+	core.after(0, next_, 1)
+
+end